Use ChromeBrowserStateManager instead of BrowserListIOS.

ios/chrome/test/app/chrome_test_util.mm

Index: ios/chrome/test/app/chrome_test_util.mm
diff --git a/ios/chrome/test/app/chrome_test_util.mm b/ios/chrome/test/app/chrome_test_util.mm
index 0f9fbcaf8d20c7259e0b3477ed4eed2d880f5ec7..9f43f5a729f2b27a9ccd6e1ef9523680d20880f8 100644
--- a/ios/chrome/test/app/chrome_test_util.mm
+++ b/ios/chrome/test/app/chrome_test_util.mm
@@ -16,10 +16,10 @@
 #import "ios/chrome/app/main_controller_private.h"
 #include "ios/chrome/browser/application_context.h"
 #include "ios/chrome/browser/browser_state/chrome_browser_state.h"
+#include "ios/chrome/browser/browser_state/chrome_browser_state_manager.h"
 #import "ios/chrome/browser/metrics/previous_session_info.h"
 #import "ios/chrome/browser/metrics/previous_session_info_private.h"
 #import "ios/chrome/browser/tabs/tab.h"
-#import "ios/chrome/browser/ui/browser_list_ios.h"
 #import "ios/chrome/browser/ui/browser_view_controller.h"
 #import "ios/chrome/browser/ui/commands/UIKit+ChromeExecuteCommand.h"
 #import "ios/chrome/browser/ui/commands/generic_chrome_command.h"
@@ -65,14 +65,17 @@ Tab* GetCurrentTab() {
 // Returns the original ChromeBrowserState if |incognito| is false. If
 // |ingonito| is true, returns an off-the-record ChromeBrowserState.
 ios::ChromeBrowserState* GetBrowserState(bool incognito) {
-  DCHECK(!BrowserListIOS::empty());
-  id<BrowserIOS> browser = *BrowserListIOS::begin();
-  DCHECK(browser);
-  ios::ChromeBrowserState* browser_state = [browser browserState];
-  DCHECK(browser_state);
-  browser_state = incognito ? browser_state->GetOffTheRecordChromeBrowserState()
-                            : browser_state->GetOriginalChromeBrowserState();
-  return browser_state;
+  std::vector<ios::ChromeBrowserState*> browser_states =
+      GetApplicationContext()
+          ->GetChromeBrowserStateManager()
+          ->GetLoadedBrowserStates();
+  DCHECK(!browser_states.empty());
+
+  ios::ChromeBrowserState* browser_state = browser_states.front();
+  DCHECK(!browser_state->IsOffTheRecord());
+
+  return incognito ? browser_state->GetOffTheRecordChromeBrowserState()
+                   : browser_state;
 }
 
 // Gets the root UIViewController.